It all sounds pretty solid to me. As a fellow FL user, I like the sound of your music and actually have very little advice that would be useful ^_^; these may be good to try on though:
- Spread out your selection of plugins a little. FL Slayer has some pretty good guitars, Drummaxx & FPC are both good for drums, and Harmless & Ogun are also very neat.
And of course, Fruity Soundfont Player is all you really need for most things- Tweak the presets on Sytrus a little. It's pretty amazing what you can come up with by fiddling around with knobs and dials for a few minutes.
That aside, the only real advice I have is to try and deviate from the originals a little. This isn't necessarily saying you're too faithful to the original material of course; sometimes an arrange is better than an outright remix. But there are some times when an arrange might not cut it, like with Rigid Paradise. A remix is pretty much a song reimagined by the one mixing it, and I've got an example with large amounts of shameless self-advertising.
See:
ZUN +
UnendingEmpire =
thisAll that said, I should re-establish that you know how to work the software quite well and seem to be doing pretty well
I look forward to future releases and will now proceed to wipe the dust off my Soundcloud account